Using data from the crowdsourced database eBird, Harry Stevens mapped the shifts in bird populations for the Washington Post. Increased building and climate change have led to population declines for many species over the past decade, but some species, such as the blue jay, have seen growth.
Be sure to check out the interactive at the end that lets you search the full species list.
Diligent birders log data on eBird, which they can use to keep track of their own observations. Collectively, researchers can then generate reliable models with the data. The scale of this project continues to amaze.